Asynchronous Threading

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Introduction

This code demonstrate how easily one can create a asynchronouse processes using .net threading.

Why Use Asynchronouse Threading:

Let' say you have a budle of requests to save data then you need to use threading
other wise system will wait for first request to be completed and then awoke function  for sencond request.

By using threading always a new instance of of your function will be created and many instances will be running togeather, and data will be saved parrally from application end.

What you have to do:

Create a function that will be called rapidly.
Suppose 

void 
SaveUser(int id,string name){...} 

Now create a function that will create thread and add this function to it...

void dosave(id,name){<P></P>
<P>t=<FONT color=#0000ff>new</FONT> Thread (<FONT color=#0000ff>new</FONT> 
ThreadStart(SaveUser(id,name)));</P>
<P>}</P>

On each request of save data call above function...

dosave(1,"jhon smith");<P></P>

What you have to include to use threading

You have to include threading name space in order to use the threading class.

using System.Threading;

Form1.cs

<FONT color=#0000ff><P></FONT> </P><P><FONT color=#0000ff>private</FONT> <FONT color=#0000ff>void</FONT> Form1_Load(<FONT color=#0000ff>object</FONT> sender, System.EventArgs e)</P><P>{</P><P>//to track maximum request count</P><P></P><P></P><P></P><P>count=0;</P><P>//set text for button 1</P><P>button5.Text ="Start Thread 1 ";</P><P></P><P>}</P><P><FONT color=#0000ff>private</FONT> <FONT color=#0000ff>void</FONT> button5_Click(<FONT color=#0000ff>object</FONT> sender, System.EventArgs e)</P><P>{</P><P> </P><P>//incremnet in count and maximun count can be 4</P><P></P><P></P><P></P><P><FONT color=#0000ff>if</FONT> ((count+1)<=4){</P><P></P><P>count++;</P><P></P><P></P><P></P><P><FONT color=#008000>//create a new theread that will start function "StartThread"</P></FONT><P>t=<FONT color=#0000ff>new</FONT> Thread (<FONT color=#0000ff>new</FONT> ThreadStart(StartThread));</P><P><FONT color=#008000>//add thread to a hash table so that you can handle each instance of the thread.</FONT></P><P>threadHolder.Add(threadCount++,t);</P><P><FONT color=#008000>//Give some name to thread</FONT></P><P>t.Name = "Thread ID: "+threadCount;</P><P>t.IsBackground = <FONT color=#0000ff>true</FONT>;</P><P><FONT color=#008000>//Start thread</FONT></P><P>t.Start();</P><P></P><P></P><P></P><P></P><P></P><P>}</P><P></P><P><FONT color=#0000ff>if</FONT> ((count+1)<5)</P><P>{button5.Text ="Start Thread " + ((count+1)) ;}</P><P><FONT color=#0000ff>else</P></FONT><P>{ </P><P>button5.Text ="All Threads Started";</P><P>button5.Enabled =<FONT color=#0000ff>false</FONT>;</P><P>}</P><P> </P><P>}</P><P> </P><P> </P><P> </P><P><FONT color=#0000ff>private</FONT> <FONT color=#0000ff>void</FONT> StartThread()</P><P>{</P><P><FONT color=#008000> </FONT></P><FONT color=#008000><FONT color=#008000><P><FONT color=#008000>//create instance form to show repation of thread</P></FONT></FONT><P><FONT color=#008000> </P></FONT></FONT><P>Form2 frm=<FONT color=#0000ff>new</FONT> Form2();</P><P>frm.Show ();</P><P></P><P><FONT color=#0000ff>int</FONT> localCopy=count; </P><P><FONT color=#0000ff>int</FONT> WR=0;</P><P><FONT color=#0000ff>string</FONT> sW="";</P><P><FONT color=#008000>//run always </FONT></P><P><FONT color=#0000ff>while</FONT>(<FONT color=#0000ff>true</FONT>)</P><P>{</P><P></P><P>WR++;</P><P>sW=WR.ToString(); </P><P>frm.Text="Thread " + localCopy + " (Repeat=" + sW + ")" ; </P><P></P><P><FONT color=#008000>//give some break</FONT></P><P>Thread.Sleep(100); </P><P><FONT color=#0000ff>try</P></FONT><P>{ </P><P> </P><P><FONT color=#008000>//change back colors to show thread is running</FONT><P></P><FONT color=#0000ff>switch</FONT> (localCopy)<P></P><P></P><P>{</P><P><FONT color=#0000ff>case</FONT> 1:</P><P></P><P><FONT color=#0000ff>if</FONT> (<FONT color=#0000ff>this</FONT>.button1.BackColor==Color.Red ) </P><P><FONT color=#0000ff>this</FONT>.button1.BackColor=Color.Green;</P><P><FONT color=#0000ff>else</P></FONT><P><FONT color=#0000ff>this</FONT>.button1.BackColor=Color.Red;</P><P></P><P> </P><P><FONT color=#0000ff>break</FONT>;</P><P><FONT color=#0000ff>case</FONT> 2:</P><P></P><P><FONT color=#0000ff>if</FONT> (<FONT color=#0000ff>this</FONT>.button2.BackColor==Color.Red ) </P><P><FONT color=#0000ff>this</FONT>.button2.BackColor=Color.Green;</P><P><FONT color=#0000ff>else</P></FONT><P><FONT color=#0000ff>this</FONT>.button2.BackColor=Color.Red;</P><P><FONT color=#0000ff>break</FONT>;</P><P><FONT color=#0000ff>case</FONT> 3:</P><P></P><P><FONT color=#0000ff>if</FONT> (<FONT color=#0000ff>this</FONT>.button3.BackColor==Color.Red ) </P><P><FONT color=#0000ff>this</FONT>.button3.BackColor=Color.Green;</P><P><FONT color=#0000ff>else</P></FONT><P><FONT color=#0000ff>this</FONT>.button3.BackColor=Color.Red;</P><P><FONT color=#0000ff>break</FONT>;</P><P><FONT color=#0000ff>case</FONT> 4:</P><P></P><P><FONT color=#0000ff>if</FONT> (<FONT color=#0000ff>this</FONT>.button4.BackColor==Color.Red ) </P><P><FONT color=#0000ff>this</FONT>.button4.BackColor=Color.Green;</P><P><FONT color=#0000ff>else</P></FONT><P><FONT color=#0000ff>this</FONT>.button4.BackColor=Color.Red;</P><P><FONT color=#0000ff>break</FONT>;</P><P>}</P><P> </P><P></P><P></P><P></P><P></P><P>}</P><P></P><P><FONT color=#0000ff>catch</FONT>(Exception e1)</P><P>{</P><P>Console.WriteLine("Exception Form1 loop >> "+e1);</P><P><FONT color=#0000ff>break</FONT>; </P><P>}</P><P>}</P><P>}</P><P></P><P></P><P> </P><P>}</P><P> </P><P>}</P>

Form2.cs

This form shows the no of time for which a single process is repeating.